1/*$NetBSD: dm_target_mirror.c,v 1.24 2020/01/21 16:27:53 tkusumi Exp $*/ 2 3/* 4 * Copyright (c) 2009 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Adam Hamsik. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31#include <sys/cdefs.h> 32__KERNEL_RCSID(0, "$NetBSD: dm_target_mirror.c,v 1.24 2020/01/21 16:27:53 tkusumi Exp $"); 33 34/* 35 * This file implements initial version of device-mapper mirror target. 36 */ 37#include <sys/types.h> 38#include <sys/param.h> 39#include <sys/buf.h> 40 41#include "dm.h" 42 43/* dm_target_mirror.c */ 44int dm_target_mirror_init(dm_table_entry_t *, int, char **); 45char *dm_target_mirror_table(void *); 46int dm_target_mirror_strategy(dm_table_entry_t *, struct buf *); 47int dm_target_mirror_sync(dm_table_entry_t *); 48int dm_target_mirror_destroy(dm_table_entry_t *); 49//int dm_target_mirror_upcall(dm_table_entry_t *, struct buf *); 50 51typedef struct target_mirror_config { 52#define MAX_MIRROR_COPIES 4 53 dm_pdev_t *orig; 54 dm_pdev_t *copies[MAX_MIRROR_COPIES]; 55 56 /* copied blocks bitmaps administration etc*/ 57 dm_pdev_t *log_pdev; /* for administration */ 58 uint64_t log_regionsize; /* blocksize of mirror */ 59 60 /* list of parts that still need copied etc.; run length encoded? */ 61} dm_target_mirror_config_t; 62 63#ifdef DM_TARGET_MODULE 64/* 65 * Every target can be compiled directly to dm driver or as a 66 * separate module this part of target is used for loading targets 67 * to dm driver. 68 * Target can be unloaded from kernel only if there are no users of 69 * it e.g. there are no devices which uses that target. 70 */ 71#include <sys/kernel.h> 72#include <sys/module.h> 73 74MODULE(MODULE_CLASS_MISC, dm_target_mirror, "dm"); 75 76static int 77dm_target_mirror_modcmd(modcmd_t cmd, void *arg) 78{ 79 dm_target_t *dmt; 80 int r; 81 82 switch (cmd) { 83 case MODULE_CMD_INIT: 84 if ((dmt = dm_target_lookup("mirror")) != NULL) { 85 dm_target_unbusy(dmt); 86 return EEXIST; 87 } 88 dmt = dm_target_alloc("mirror"); 89 90 dmt->version[0] = 1; 91 dmt->version[1] = 0; 92 dmt->version[2] = 0; 93 dmt->init = &dm_target_mirror_init; 94 dmt->table = &dm_target_mirror_table; 95 dmt->strategy = &dm_target_mirror_strategy; 96 dmt->sync = &dm_target_mirror_sync; 97 dmt->destroy = &dm_target_mirror_destroy; 98 //dmt->upcall = &dm_target_mirror_upcall; 99 100 r = dm_target_insert(dmt); 101 102 break; 103 104 case MODULE_CMD_FINI: 105 r = dm_target_rem("mirror"); 106 break; 107 108 case MODULE_CMD_STAT: 109 return ENOTTY; 110 111 default: 112 return ENOTTY; 113 } 114 115 return r; 116} 117#endif 118 119/* 120 * Init function called from dm_table_load_ioctl. 121 * start length mirror log_type #logargs logarg1 ... logargN #devs device1 offset1 ... deviceN offsetN 122 * 0 52428800 mirror clustered_disk 4 253:2 1024 UUID block_on_error 3 253:3 0 253:4 0 253:5 0 123 */ 124int 125dm_target_mirror_init(dm_table_entry_t *table_en, int argc, char **argv) 126{ 127 128 printf("Mirror target init function called!!\n"); 129 130 table_en->target_config = NULL; 131 132 return ENOSYS; 133} 134 135/* Table routine called to get params string. */ 136char * 137dm_target_mirror_table(void *target_config) 138{ 139 140 return NULL; 141} 142 143/* Strategy routine called from dm_strategy. */ 144int 145dm_target_mirror_strategy(dm_table_entry_t *table_en, struct buf *bp) 146{ 147 148 bp->b_error = EIO; 149 bp->b_resid = 0; 150 151 biodone(bp); 152 153 return 0; 154} 155 156/* Sync underlying disk caches. */ 157int 158dm_target_mirror_sync(dm_table_entry_t *table_en) 159{ 160 161 return 0; 162} 163 164/* Doesn't do anything here. */ 165int 166dm_target_mirror_destroy(dm_table_entry_t *table_en) 167{ 168 169 /* Unbusy target so we can unload it */ 170 dm_target_unbusy(table_en->target); 171 172 return 0; 173} 174 175#if 0 176/* Unsupported for this target. */ 177int 178dm_target_mirror_upcall(dm_table_entry_t *table_en, struct buf *bp) 179{ 180 181 return 0; 182} 183#endif 184